Because pesticides must be applied yearly, they are best-used to protect high value trees or to keep individual ash alive until non-susceptible replacement trees are large enough to provide shade benefit.

A severely compromised ash tree, regardless of the cause of its poor condition, is not a good candidate for preventative or curative treatment.

Property owners should take the long term cost of prevention into account decide when deciding whether to use pesticides to protect their ash trees from EAB. Since ash trees must be treated every year for an indefinite period, the cost of chemical protection may quickly exceed the cost of removing and replacing them.

J. Ellis, Purdue

This ash tree, although not infested with EAB, suffers from site issues and is not a good choice for preventative treatment.

J. Ellis, Purdue

This EAB-infested ash tree is not a good candidate for treatment.

R. Lerner, Purdue

A healthy ash tree such as this is an excellent candidate for preventative treatments.